Clamp for derrick legs



July 12, 1932. J. D. M EWEN CLAMP FOR DERRICK LEGS Filed July 25, 1928 2Sheets-Sheet 1 WITNESSES Madurai.

July 12, 1932. J. D. M EWEN CLAMP FOR DERRICK LEGS Filed July 25, 1928 2Sheets-Sheet 2 w'rmessas Patented July 12 1932 UNIT sr'rs FAT -1" pfi-gj JOHN D. MCEWEN, or PITTSBURGH,.PENKSYLVANIA, assmnon To LEE 0.MOORE &

' COMPANY, INC., on PITTSBURGH, PENNSYLVANIA, A conronarron or PENNSYL:

VANIA CLAMP FOR DERRICK LEGS Application filed July 25,

This invention relates to clamps for connecting adjacent ends of tubularleg sections of derrick structures used in oil well drilling, and thelike.

The objects of the invention are to provide a clamp of strongerstructure than has heretofore been used and capable of more economicmanufacture An object of the invention is to make the major portion ofthe clamp of one or more rolled steelplates. 'Anotherobject is to avoidthe necessity of striking up flanges from the body of the plates forattachment of girts and braces to the clamps formed thereof. Anothervobject is to provide a multi-plate clamp, in which the several partsmaybe manufactured'to best advantage, the whole being rigidly united bywelding, casting, or riveting, to give the strength of a unitarystructure, with a reduction of cost. .Other objects and vadvantages willbe apparent to those familiar with the art from the specification anddrawings. 1 1 a Referring to the drawings, Fig. 1- is a plan view of apreferred form of the clamp; Fig. 2 is a partial side view thereof,showing the perforations of one of the radial flanges; Fig. 3 is a sideelevation of the clamp showing one of the main plate members'complete;Fig. 4 is a plan view of amodification in which the connecting plate isriveted tothe main pair ofplates; Fig. 5 is a view of the modifiedconnecting plate of Fig- 4; Fig. 6 is a modification in whichthe 'mainplates are connectedby a cast member which is adapted to support an.attachment for a releg structure; Fig. 7 is a partial section on theline V1 VI of 5; Fig. 8"is amodification showing the entire tubular por-1-;- tion of the clamp formed from a single ribbed plate with the radialflanges formed ofseparateplates welded thereto; Fig. 9 is anend view ofa special plate for forming the tubular portion of the clamp of Fig. 8;Fig.

10 is a partial view similar to that of Fig. 1, showing-a modified formof welding; and Fig. 11 is a partial View similar to that of Fig. 1,showing the clamping flanges as compressed after considerable usage.

an The derricks used in drilling wells foroil,

192s. Serial no. 295,150.

' gas, water, etc. are now preferably made of them morehighlydeveloped,there has been increased necessity for derrick strength.

Such derricks are ordinarily formed of four cornerposts arranged inpyramidal order, connected together by bolted-on trans.- verse girts andbra.ces, the legs being formed of abutting aligned sections. of steeltubing,

the adj acent.endsthereof being connectedby clamps. This, latter elementis the portion of such derricks to which the present inven tion isaddressed. I

Derricks of this kind are made of standard interchangeable parts, sothat. they may be erected and dismantled withoutspecial maichinery ortools, and so that any broken, dam,- aged, or lost parts may be readilyreplaced, from stock. In erecting the derricks the 76 structure israisedfromthe ground upon itself, without scaffolding, two or moreworkmen building it up, or taking it down progressively from bottom totop, or vice versa.

With the modern tendency to. heavier structures, caused by deeperdrilling and more powerful drilling rigs, the strength of all parts hasbecome increasingly important. The present clamp is adapted toobviatesome of the weaknesses of prior pressed steel clamps. Forex ample itdoes away with the weakening ofsuch clamps resulting from the strikingup of large portions thereof for .the purpose of forming flanges for theattachment of girts and braces. That method of manufacture has beenprevalent in the best clamps of the prior art.

The present structure permitsthe forming I of the major portions of theclamp from standard structural plate material, sheared to size,perforated and bent to shape by suitable dies operating in a singledirection, and without unduly straining themetal in the forming thereof.Since no part of these plates is struck up or cut out to form "attach- Yment flanges for girts and braces, a Wide area is provided in whichperforations for receiving diametric through-bolts may be made, withoutmaterially weakening the 1 clamp structure.

Referring to Fi-g.- 1 of the drawings, the preferred form oftheinvention is illustrated as comprising a pair of similarcomplementary plates 1, 1. Thesehave the portions intermediate theirlateral edges formed into arcuate segmental tubular shape, adapted toseat upon a concentric tubular leg section therein when in operativeposition. Adjacent lateral edges of the main plates are bent out-.wardly to form radial flanges 2, 2, the other two. lateral edges of themain-plates beingbent to form parallel spaced-apart flanges 3. Theradial. flanges have an inner series of c1rcu-lar perforations t. and anouter series of arcuate slots 5, the latter being concentric with theholes 4, so that when girts'and braces of. the tower structure which areadapted to be attached to the flanges 2 by means of the perforationsreferred to, are in position, the inner endsbeing retained by attachmentbolts passing through the holes l, the outer ends will haveaconsiderable range of vertical adjustment because of the play ofattachment bolts in the arcuate slots 5. V I

The flanges 3 on the other lateral edges of the plates, herein referred;to as theparallel flanges, are also perforated, having oval, square orpreferably circular holes 6 therein. These are adapted to receivecompression bolts? for drawing the clamp tight upon the adjacent ends oftubular leg sections 9, as indicated in Fig. 1'. Preferably the flanges3 are made wide enoughso thatafter they have been useda few times theirouter edges may contact as shown in Fig. 11. 'Thereafter all low themiddle transverse planeof the clamp. These are for the purpose ofreceiving through-boltslO adapted to pass throughv the clampdiametrically and through the adjacent; endsv of the tubular legsections,,which normally meet in the median transverse plane of theclamp- These perforations. for the through-bolts are preferablyelongated as :ShOIVIl.

This: shape. isfor the purpose of making iteasier to get the boltsthrough the opposite side of the clamp from which it has beeninserted.,One advantage ofthepresent form of multi-plate clampis that it provides"ample space in the clamp body fOIgtllGSG elongated through-boltopenings without un dulyweakening the clamp structure.

l The main plate members 1 are made in. sim ilar pairs, so that they areinterchangeable in making up the olamp,.it only being necesof this thirdplate member are, bent outward radially and are adapted to lie againstand parallel withthe bases of the radialflanges 2 of the main platemembers. These parallel abutting flanges. are then welded togetherelectrically as indicated at 12, 12, of Fig. 1, or 12a, 12a, of Fig. 10.In Fig. 1 the plates are spot welded at three onmore points. In Fig. 10the plates are arc welded along the entire outer edge of plate 11, andin addition they are welded at thetop and bottom 'ontheinside asindicated at 12b, 12b. The result is the forming of three plates 1, 1,and 11 into a rigid integral plate structure havinga tubular portion forengaging tubular leg sections, having outstanding radialflanges forengaging girts and braces, and

having outstanding flanges '3, 3, for receivmg compression bolts '7 forfirmly securing the clamp upon the ends of the leg sections. In erectingsuch derricksa clamp is slipped down on the top of a section of a legand the lower through-bolt put through the clamp and through the top ofthe leg section, the compressionbolts are put in and the lowermost ofthe compression bolts 7 is tightened up somewhat. Thisis'done ontheground. This leg section with clamp attached tothe upper end is then.hoisted to the support of the derrick and its'free end seated inthe openclamp of a previously positioned section. Girts and braces leading fromthe other legs of the derrick are attached by 'upon' the first andinside the clamp, resting uponthe upper end of the first mentionedsection. Asecondthrough bolt is putthrough theclamp'and through thelower end of the second leg section, the second and third compressionbolts 7 are inserted and drawn tight, andsoon. i

Figs. 4: and 5 show a modification in that the main plates 1a. 1a, whileof substantially the same shape and arrangement as the plates 1 of 1.are perforated at and through the basesof the radial flanges 2a, 2a. Athird plate 1101. has tongues formed in each lateral edge, adapted toextend through'the perforations of the plates 1a. These tongues thenhave their terminals upset beyond the plates 1a to form riveted heads21, as shown in Fig. 4. The intermediate portion of the plates 11a isbent into tubular segmental the tongues, in a suitable mold, forming arigid connection between the plates 1?) and enclosing the tongues in.thecasting 26. The inner portion of this cast connectionmember is ofsegmental tubular form continuous and concentric with the curvedportions of the plates 1?). The outer portion of the cast member 26 hasan arcuate longitudinal portion 27, adapted to seat a tubular relegsection. Straight faces 28 on the outer side of the casting 26 areadapted to receive terminal flanges 29 of a clamping band 30 adapted toenclose the releg tube section 31. The casting is bored 'to receivescrews 32 adapted to extend through the flanges 29 and to be threadedinto said bores in the casting for retaining the band 30 thereto. Theplates 17) are provided with openings 86 positioned as and for thepurpose of the openings 8 of Fig. 3.

Another modification is shown in Figs. 8 and 9. wherein a clamp isillustrated as made up of a special plate 40 having longitudinalparallel spaced apart ribs 41 on one side thereof. The plate 10 is bentupon itself as shown in Fig. 8, the lateral edges being bent outwardlyto form parallel spaced apart flanges 30, having perforations 60, forreceiving compression bolts as in the other forms of the clamp. The ribs41 are positioned on the side of the clamp opposite the compressionflanges 30. Flange-plates 20 are buttwelded to the ribs 41 so as toextend radially therefrom. These flange-plates are perforated to provideholes for receiving attachment bolts as shown in Fig. 2. Through-boltopenings are provided on each side of the median plane of the clamp. Bythis modification the main clamp body is made of a single plate, and theflanges for attaching girts and braces are provided by separatewelded-on plates without the necessity of weakening the clamp body bystriking up or cutting out any portion thereof. The buttwelded flangeplates are thusmade integral with the main plate. The result is averystrong, comparatively light, all-plate unitary clamp.

Distinct advantages from the point of view of manufacturing expediency,cost, and

strengthpof these clamps made mostly of rolled structural plate stockwill be apparent to those familiar with the art.

I claim: 7

1. A clamp for joining tubular leg sections of oil well derricks,comprising a pair of similarv plates pressed intermediate their lateraledges to form tubular segments and having their lateral edges bent toform outstanding flanges, said flanges being perforated to receiveattachment bolts, and an intermediate member permanently and rigidlyconnecting the plates to form a. unitary clamp.

2. A clamp for tubular leg sections of oil well derricks, comprising apair of similar plates pressed intermediate their lateral edges to formtubular segments and. each having one lateral edge bent radially to forman outstanding'flange for attachment of girts and braces, the two radialflanges being connected by a third segmental plate having its lateraledges bent outward radially to form flanges adapted to bear against theradial flanges of the first mentioned plates, said contacting flangesbeing welded together to unite the three platesinto a unitary clamp.

3. A clamp for tubular leg sections of oil well derricks comprising apair of similar plates pressed intermediate their lateral edges to formtubular segments and each having one lateral edge bent radially to forman outstanding flange for attachment ofgirts and braces, the otherlateral edges being bent to form parallel flanges adapted to beconnected by clamping bolts, the two radial flange-s beingconnected by athird segmental plate having its lateral edges bent outward radially toform flanges adapted to bear against the radial flanges of the firstmentioned plates, said contacting flanges being welded together to unitethe three plates into a unitary clamp. v

In testimony whereof, I sign my name.

JOHN D. MCEWEN.

